1. Field of the Invention
Further, the present invention relates to a network, preferably for carrying out the above method, wherein at least one end user device is connected to an access network.
2. Description of the Related Art
Today's access networks such as broadband or xDSL (x Digital Subscriber Line) networks and the devices connected to them have very particular properties that can significantly influence the performance of the network or Internet access as seen by the applications running on end user devices such as laptops and PCs. An end user device or system today has only limited means to address this issue as the information that would help to tune network stack parameters accordingly is not available as they do not directly connect to the access network but typically a home gateway or modem would connect to the access network on the one side and to a home network—often wireless LAN (Local Area Network), 802.11—on the other side. A, to a certain degree, similar problem can be found in the access networks today, where the DSL modem negotiates a rate with the MSAN/DSLAM (Multi Service Access Node/Digital Subscriber Line Access Multiplexer). The BRAS (Broadband Remote Access Server) needs this lower layer information for QoS (Quality of Service) provisioning and accounting. A protocol has been devised to deal with this issue called ANCP (Access Node Control Protocol), see ANCP, http://tools.ietf.org/wg/ancp/. Other protocols in the access network space are far from fulfilling this role, such as TR-69, see http://www.broadband-forum.org/technical/download/TR-069Amendment2.pdfl, as they are used to operate and manage the home gateway, which is still (at least) one IP hop away from the end user device where the access network visibility is missing.
The problem described here is the problem of resource consumption of for example background applications such as P2P (Peer-to-Peer) and interactive applications such as VoIP (Voice over Internet Protocol), Web browsing, gaming and others. The problem specifically is that background traffic should always yield to interactive traffic, i.e. it should stop or slow down the resource consumption, i.e. sending traffic, once interactive applications need it. In the IETF (Internet Engineering Task Force), the Low Extra Delay Background Traffic (LEDBAT) working group is dealing with these issues, see IETF LEDBAT working group, http://www.ietf.org/html.charters/ledbat-charter.html. But the IETF approach is a so called end-to-end approach, which does not rely on information that the access network and the devices in it or attached to it can provide.
The congestion control algorithm proposed in S. Shalunov, “Low Extra Delay Background Transport (LEDBAT)”, http://tools.ietf.org/html/draft-shalunov-ledbat-congestion in the LEDBAT context tries to minimize the extra delay that background applications such as P2P add to interactive applications such as VoIP. It does so by estimating the delay it introduces. This delay is usually due to the modem buffer in the home gateway these days. Additionally, the base technology of the access network is important. E.g. in case ATM (Asynchronous Transfer Mode) is used, also quite common today, the algorithm could be optimized to send segments that exactly fill the ATM cells. Assuming small upstream bandwidths (below approx. 500 kbps), this could help to lower the probability of unnecessary head of line blocking. These are all what we call lower layer information of the access network itself (e.g. technology used with bandwidth and cell sizes) and the devices in it or attached to it (e.g. buffer sizes).
It is to be noted that U.S. Pat. No. 7,051,087—System and method for automatic detection and configuration of network parameters—deals with a different issue then the present invention. This U.S. Pat. No. 7,051,087 deals with changing networks and their required re-parameterization, and it makes a claim about a home network and an enterprise network where one has a static IP and the other a dynamic one. The user needs to manually switch from one to the other.
In PONs (Passive Optical Network) upstream sender timeslots on the shared PON are assigned by quite sophisticated algorithms taking into account e.g., measurements on a frame level (layer 2), see Cauvin et al., Common Technical Specification of the G-PON System among Major Worldwide Access Carriers, IEEE ComMag October 2006, and references therein and Assi et al., “Toward Quality of Service Protection in Ethernet Passive Optical Networks: Challenges and Solutions” in IEEE ComMag September/October 2007, and references therein. With this method, the access network can inform the endpoints that are unaware of the access network about its specific, current paramterization which can enable the IP endpoints to adapt their sending behavior exactly to the learned boundary conditions, e.g. send packet bursts that exactly fit into timeslots in order to prevent them from dynamically growing and shrinking.